1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * latencytop.h: Infrastructure for displaying latency
4 *
5 * (C) Copyright 2008 Intel Corporation
6 * Author: Arjan van de Ven <arjan@linux.intel.com>
7 *
8 */
9
10 #ifndef _INCLUDE_GUARD_LATENCYTOP_H_
11 #define _INCLUDE_GUARD_LATENCYTOP_H_
12
13 #include <linux/compiler.h>
14 struct task_struct;
15
16 #ifdef CONFIG_LATENCYTOP
17
18 #define LT_SAVECOUNT 32
19 #define LT_BACKTRACEDEPTH 12
20
21 struct latency_record {
22 unsigned long backtrace[LT_BACKTRACEDEPTH];
23 unsigned int count;
24 unsigned long time;
25 unsigned long max;
26 };
27
28
29
30 extern int latencytop_enabled;
31 void __account_scheduler_latency(struct task_struct *task, int usecs, int inter);
32 static inline void
account_scheduler_latency(struct task_struct * task,int usecs,int inter)33 account_scheduler_latency(struct task_struct *task, int usecs, int inter)
34 {
35 if (unlikely(latencytop_enabled))
36 __account_scheduler_latency(task, usecs, inter);
37 }
38
39 void clear_tsk_latency_tracing(struct task_struct *p);
40
41 int sysctl_latencytop(struct ctl_table *table, int write, void *buffer,
42 size_t *lenp, loff_t *ppos);
43
44 #else
45
46 static inline void
account_scheduler_latency(struct task_struct * task,int usecs,int inter)47 account_scheduler_latency(struct task_struct *task, int usecs, int inter)
48 {
49 }
50
clear_tsk_latency_tracing(struct task_struct * p)51 static inline void clear_tsk_latency_tracing(struct task_struct *p)
52 {
53 }
54
55 #endif
56
57 #endif
58